A linear guide device using rollers as rolling elements generally includes a rail having a lateral left face and a lateral right face surface, a slider having a front end face and a rear end face in the longitudinal direction of the rail and end caps each attached on the front end face and the rear end face of the slider, in which slider-side raceway surfaces opposed to rail-side raceway surfaces formed on the lateral left face and the lateral right face of the rail are formed on two opposing inner lateral faces of the slider. Further, the linear guide device of this type has a plurality of rollers. The rollers are adapted to roll through rolling element rolling channels formed between the rail-side raceway surfaces and the slider-side raceway surfaces by the relative movement of the slider in the longitudinal direction of the rail. Then, the rollers rolling through the rolling element rolling channels change direction in direction changing channels for rolling elements formed in the end cap, then return to the original position through rolling element returning channels formed in the slider along the longitudinal direction of the rail, and again circulate the path described above.
In the linear guide device described above, in a case where a succeeding roller collides against the preceding roller, it may possibly generate sounds or deteriorate the operating performance of the slider. In view of the above, in the linear guide device disclosed in JP2001-132745A, a retaining piece made of resin is interposed between each of the rollers thereby preventing occurrence of noises or deterioration of the operating performance caused by collision between each of the rollers.
However, in a case where the distance between the two adjacent rollers increases during movement of the slider, the retaining piece is in contact with the rail-side raceway surface or the slider-side raceway surface and the retaining piece suffers from early wear to result in a problem of shortening the life of the retaining piece. In addition, the retaining piece is deformed by the contact of the retaining piece with the rail-side raceway surface, the slider-side raceway surface, etc. to possibly deteriorate the operating performance of the slider.